I ordered a replacement freewheel for a small kids bike. It is labelled as 1/2″ x 1/18″. (18tooth rather than the 17tooth of the original freewheel as I couldn’t find a 17tooth one). Evidently I’ve got the wrong size – I assumed all single speeds were uniform. What size should I order?
by NucleurDuck
5 Comments
You most likely need a 1/2×3/32 – all bicycle chains will have 1/2 inch pitch (how far apart are the pins from one link to the next) but they make a few wides (how fat is the tooth).
Because your chain won’t mess down with the freewheel, I have my money on this being a 3/32 version.
It looks like a narrow 3/32″ chain (aka 6/7/8 speed) while the sprocket is probably a regular 1/8″ (single speed).
Just get an 1/8″ chain and you will be sorted.
Get 2 half link BMX chains ! I ran into this problem a few times.
Order a new chain.